Warning device



June 20, 1961 MAYO ETAL 2,989,050

WARNING DEVICE Filed May 4, 1955 25 r .II J:

INVENTORS ALFRED M. MAYO HOWARD E 6ARRARO FIG. 4 BY A-- ATTORN UnitedStates Pate I 2,989,050 T WARNING DEVICE Alfred M. Mayo, Palos VerdesEstates, Calif. (6810 Clay 'St., xon.'I-Iill, Md.);' and Howard F.Garrard, 113 Sheldon Ave., El Segundo, Calif. v 1 Filed May 4, 1955,Ser. No. 506,028.

7 Claims. (Cl. 128-2) This invention relates to warning devices and moreparticularly to devices adapted to be worn by a skin diver who may besubject to a low external body pressure relative to the internal lungpressure, the device being operable to warn the skin diverof thenecessity to exhale to prevent overexpansion of his lungs.

The physiological make-up of the human body is such that the passage ofair through the glottis, namely the act of breathing, is controlled bythe nervous system in accordance with the oxygen requirements of thebody, and there are no pressure-sensitivenerves related to the lungs orother organs of the breathing system for controlling,

the breathing process. The glottis is protected or closed during the actof. swallowing by means of the epiglottis and related arytenoidcartilages, and the latter organs are so characterized as to close theglottis when the process of breathing is not taking place. Also,theseorgans tend to close the glottis when the pressure within the lungsexceeds the external body pressure as in the case of an individualbreathing under water, unless the nervous system functions to open theglottis responsively to oxygen requirements.

When an individual breathes under normal conditions the pressure of theair within his lungs corresponds substantially to the external pressuresurrounding his body. However, should the external pressure decrease, inthe absence of concurrent functioning of the nervous system to initiatethe breathing process, the glottis would be closed by the epiglottis andthe arytenoid cartilages and relatively high pressure would be trappedin the lungs. Should the pressure differential between the internal lungpressure and the relatively low external body pressure increase to ahigh value, the alveoli of the lungs will rupture allowing air bubblesto enter the blood stream, resulting in death of the individual due toocclusion of a blood vessel. This results from the absence of sensorynerves associated with the lung, such as a pain warning, to indicate tothe individual, conciously or unconsciously, the presence of relativelyhigh pressure in his lungs and the necessity to exhale.

The foregoing physiological make-up of the human body occasions the onlyreal danger attendant skin diving whether followed as a sport or as ameans of gainful employment. In skin diving the individual is notclothed in a pressurized diving suit but is only provided with a sourceof compressed breathing gas, such as air, which is supplied, by means ofa breathing regulator, directly to his lungs. The breathing regulatorautomatically operates to supply a source of breathing gas responsivelyto the.

demand of the skin diver at.a pressure regulated in accordance with theexternal body pressure. Thus, as the skin diver explores to a greaterdepth below the surface of the water, the breathing regulator functionsto increase the pressure of the breathing gas in accordance with theexternal body pressure and maintain the pressure relation.

ship required for normal breathing. However, should the skin diver swimupwardly in order to escape danger or because of an injury or while inthe pursuit of game, a

decrease in the external body pressure will result, and in lungpressure. 7 If the air trapped in the lungs builds up to a criticalvalue the lungs will rupture and death may to be wornby, a skin'diverwho may be subject to rapidly decreasing external pressures withaconcomitant relative increase of the air pressure in his lungs, operableto transmit a sensory warning to the skin diver indicative of adangerously relatively high pressure condition in his lungs.

j Still another object of the present invention is to pro vide a warningdevice of the foregoing character operable responsively to abnormalpressure differentials between the internal lung pressure and theexternal body pressure of a skin diver. 7

Still another object is to provide a warning device of the above typeoperable responsively to abnormal chest expansion of the skin diver.

A still further object of the present invention is to provide a warningdevice for use by skin divers operable to positively indicate to theskin diver the necessity of exhaling upon the skin diver moving from anarea of high external body pressure to an area of relatively lowexternal body pressure.

Other objects and features of the present invention will appear morefully below from the following detailed description considered inconnection with the accompanying drawing which discloses one embodimentof the invention. It is tobe expressly understood, however, that thedrawing is designed for purposes of illustration only and not asadefinition of the limits of the invention, reference for the latterpurpose being had to the appended claims.

In the drawing, in which similar reference characters denote similarelements through the several views:

FIG. 1 is a diagrammatic illustration of a warning device embodying theprinciples of the present invention in operative position on the body ofa skin diver, the body being shown in horizontal section;

FIG. 2 is an enlarged side elevational view, partially in section, ofthe warning device of FIG. 1, the warning device being in non-warningposition;

FIG. 3 is a view in section taken along the lines 3-3 of FIG. 2, and

'FIG. 4 is an enlarged side elevational view, partially in section, ofthe warning device of FIG. 1, the warning device being shown in warningposition.

The present invention provides a warning device adapted to be worn by askin diver who may be subject to rapidly decreasing external bodypressure with'concomitant relative increase of the internal lungpressure, operable to warn the skin diver upon the relatively highpressure in his lungs exceeding a critical value so that he may exhaleand prevent over-expansion of his lungs. According to the broad conceptsof the present invention the warning device includes a supportingstructure adapted to besecured about the body of the skin diver and asensory signal producing means mounted on the.

supporting structure. The signal producing means. is

operable to transmit to the skin diver a sensory signal indicative of anexcessive pressure differential between the external body pressure andthe internal lung pressure. The foregoing will be more fully understoodwith reference to FIG. 1 of the drawing which illustrates a warm ingdevice constructed in accordance with the principles 10 of a skindiver.

gether atthe sternum '13 and a layer of skin 14. covering the ribs andconstituting the external surface oftthe-l Patented June 20,

body. The warning device comprises an adjustable harness 15, shownwrapped around the body with its ends joined together by means of abuckle mechanism 16 in the region of the sternum, and a signal producingmechanism 17 supported by the harness. In this form of the invention thesignal producing mechanism is operable to transmit a warning to the skindiver by affecting his touch senses and, as described more fully below,includes a member adapted to be moved into sensory contact with asensitive portion of the body. The signal producing mechanism 17 is thuspositioned adjacent the front of the skin divers body, to the right orto the left of the sternum, in proper vertical relationship so that thebody contacting member is adapted to move into contact with an area ofthe external skin 14 between adjacent ribs, which area has been found topossess sufficient sensitivity for the purposes of the presentinvention. Also, in the disclosed form of the invention, the signalproducing means operates responsively to an abnormal pressuredifferential between the internal lung pressure and the external bodypressure through the harness 15 which is responsive to expansion of theskin divers chest.

Construction of the signal producing mechanism 17 and its relationshipwith the harness 15 is shown in detail in FIG. 2 of the drawing. Theharness 15 comprises an elongated strap formed of inelastic materialwith its ends, as mentioned above, joined together by means of a buckle516. At a point displaced from either side of the buckle 16, such as onthe left hand side, as viewed in the drawing, for example, the inelasticstrap 15 is provided with a portion 20 projecting outwardly away fromthe surface of the skin 14. The projecting portion 20 includes anintermediate flat portion 21 having its opposite edges joined to theouter end edges of side portions 22 and 23, the side portions beinginclined downwardly and outwardly with respect to the flat portion 21with the edges of respective inner ends being joined to the ends ofspaced portions 24 and 25 of the inelastic strap 15 lying in contiguousrelation with the external surface of the skin 14. A member 26 formed ofelastic material such as rubber, for example, is connected between thespaced portions 24 and 25 of the strap 15. The member 26 may have awidth substantially corresponding to the width of the strap 15 and alength greater than the normal distance between spaced portions 24 and25. The inside surface of the member 26 is adapted to lie flat againstthe skin 14 of the body 10 while its outside surface adjacent its endslies in contiguous relation with the inside surface of the strap 15 inthe region of the spaced portions 24 and 25. The ends of the member 26may be joined to the portions 214 and 25 by cord bindingf27, or by anyother suitable means such as rivets or stitching.

The elastic member 26 is provided with a centrally positioned opening 28defined by an upwardly extending cylindrical flange member 29 which maybe integrally formed with the elastic member. The flange member 29functions as a guide for a body contacting member 30 extending throughthe opening 28 and mounted for movement relative to the flange member.The body contacting member 30 is shown in the form of a cylindricalmember with its lower end, as viewed in the drawing, terminated in aspherical surface 31 and with its upper end terminated in a flat surfaceperpendicular to its longitudinal axis. The upper end of the bodycontacting member may be provided with a rectangular flange 32 topresent a total upper end surface corresponding to the dimensions of thelower or inside surface of the intermediate flat portion 21. The bodycontacting member is secured to the intermediate fiat portion 21 withits upper end surface in contiguous relation with the lower surface ofthe intermediate flat portion 21- by meansof a stud 33' including athreaded stem 34, adapted to enter a threaded bore 35 locatedconcentrically with the longitudinal axis of the body contacting member,and a cap 36 adapted to engage the outer surface of the intermediateflat portion 21.

In operation, the inelastic harness 15 is strapped about the body of theskin diver in the region of his chest with the signal producingmechanism 17 overlying a sensitive area of the body, as shown in FIG. 1of the drawing, for example. The harness is adjusted in accordance withthe chest size of the body so that the signal producing mechanism 17 isin the non-sensory position shown in FIG. 2 for periods of maximum chestexpansion during normal breathing. Since the harness 15 is constructedof inelastic material the spaced portions 24 and 25 will move away fromeach other upon expansion of the chest. Upon such movement of the spacedportions 24 and 25, the lower ends of the inclined side portions 22 and23 move therewith causing the intermediate flat portion 21 to move in adirection toward the plane of the harness 15. Since relative outwardmovement of the spaced portions 24 and 25 is restrained equally by theelastic connecting member 26, the spaced portions will move outwardly anequal distance away from the longitudinal axis of the body contactingmember 30. Thus, upon expansion of the chest, the body contacting memberwill move substantially along its longitudinal axis in a directiontoward the skin surface 14. Inasmuch as the body contacting member 30moves into sensory contact with the body only upon abnormal expansion ofthe chest, the elastic connecting member 26 is provided with a degree ofelasticity to substantially prevent relative outward movement of thespaced portions 24 and 25 upon normal chest expansion, while allowingsuch relative outward movement upon abnormal chest expansion. Also, theend 31 of the body contacting member may be normally spaced a sufficientdistance away from the body contacting surface of the elastic member 26so that the body contacting member only moves into sensory contact withthe body upon abnormal chest expansion. If desired, the elasticity ofthe connecting member 26 and the spacing of the end 31 of the bodycontacting member may both be considered in the design of the warningdevice to preclude a sensory contact between the body and the member 30responsively to the maximum degree of chest expansion occurring duringnormal breathing cycles.

Upon abnormal expansion of the chest, which occurs when an abnormal orexcessive pressure differential exists between the internal lungpressure and the external body pressure, upon the skin diver movingupwardly from an area of high pressure to an area of relatively lowpressure, the spaced portions 24 and 25 move away from each othercausing inward movement of the body contacting member 30 into sensorycontact with the body. FIG. 4 of the drawing illustrates the signalproducing mechanism 17 in a sensory warning position responsively tosuch abnormal chest expansion. As shown, the spaced portions 24 and 25are moved outwardly to an extreme position with respect to each othercausing the end 31 of the body contacting member 30 to move inwardlybeyond the skin contacting surface of the elastic connecting member 26and into contact with the body. By positioning the harness relative tothe body so that inward movement of the body contacting member contactsa sensitive portion of the body, such as the portion between adjacentribs as shown in FIG. 3, a positive sensory indication is transmitted tothe skin diver indicative of the abnormal chest expansion and warningthe skin diver that he should exhale.

Although only one embodiment of the invention has been disclosed anddescribed herein, it is to be expressly understood that various changesand substitutions may be made therein, as described above, withoutdeparting from the spirit of the invention as well understood by thoseskilled in the art. Reference therefore will be had to the appendedclaims for a definition of the limits of theinvention.

What is claimed is:

l. A warning device adapted to be worn by a skin diver who may besubject to a low external body pressure relative to internal lungpressure, comprising signal producing means, the signal producing meansincluding an element operable to produce a sensory signal, supportingmeans adapted to be secured to a portion of the body of the skin diverto support the element at said portion in sensory relation therewith,and means operative responsively to an abnormal expansion of the chestof the skin diver for operating the element of the signal producingmeans to produce a sensory signal and warn the skin diver that he mustexhale to prevent over-expansion of his lungs.

2. A Warning device as defined in claim 1 in which the means operativeresponsively to abnormal expansion of the chest of the skin diverincludes the supporting means.

3. A warning device adapted to be worn by a skin diver who may besubject to a low external body pressure relative to the internal lungpressure, comprising signal producing means, the signal producing meansincluding an element, supporting means adapted to be secured to aportion of the body of the skin diver to support said element at saidportion in sensory relation therewith, the element having an operatingstate and a non-operating state and being operable from one state to theother state and the element in the operating state producing a sensorysignal which is imparted to said portion of the body of the skin diver,means for normally maintaining the element in the non-operating state,and means operative responsively to an abnormal expansion of the chestof the skin diver to operate the element to the operating state andthereby warn the skin diver that he must exhale to preventover-expansion of his lungs.

4. A warning device adapted to be worn by a skin diver who may besubject to a low external body pressure relative to internal lungpressure, comprising signal producing means, the signal producing meansincluding an element, supporting means adapted to be secured to aportion of the body of the skin diver to support the element at saidportion, the element being operable for movement into contact with saidportion of the body of the skin diver to transmit a sensory warning tothe skin diver, and means operative responsively to an abnormalexpansion of the chest of the skin diver for operating the element towarn the skin diver that he must exhale to prevent over-expansion of hislungs.

5. A warning device adapted to be worn by a skin diver who may besubject to a low external body pressure relative to the internal lungpressure, comprising signal producing means, the signal producing meansincluding a movable element, supporting means adapted to be secured to aportion of the body of the skin diver for supporting the element at saidportion, the element being movable between a first position out ofcontact with said portion of the body of the skin diver and a secondposition in contact with said portion of the body of the skin diver toimpart a sensory warning to the skin diver, means normally maintainingthe element in the first position, and means operative responsively toabnormal expansion of the chest of the skin diver to move the element tothe second position and warn the skin diver that he must exhale toprevent over-expansion of his lungs.

6. A warning device adapted to be worn by a skin diver who may besubject to a low external body pressure relative to the internal lungpressure, comprising an inelastic strap adapted to be positioned aroundthe body of the skin diver in the region of the chest, the inelasticstrap including spaced relatively movable portions, signal producingmeans mounted on the inelastic strap in the region of the spacedrelatively movable portions and connected to the spaced relativelymovable portions, the signal producing means including a movable membermovable between a first position out of sensory contact with the chestof the skin diver and a second position in sensory contact with thechest of the skin diver, means for normally maintaining the movablemember in the first position, means for moving the movable member to thesecond position, and means responsive to relative outward movement ofthe spaced relative movable portions of the inelastic strap foroperating the last-named means to warn the skin diver that he mustexhale to prevent overexpansion of his lungs.

7. A warning device adapted to be worn by a skin diver who may besubject to a low external body pressure relative to the internal lungpressure to warn the skin diver that he must exhale to preventover-expansion of his lungs, comprising an inelastic strap having firstand second surfaces, means to secure the inelastic strap in chestencircling position, the inelastic strap including a flexible loopportion projecting outwardly from the first surface to present spacedend portions of the inelastic strap, an elastic member connected to thespaced end portions of the inelastic strap to bridge the space betweenthe spaced end portions, the elastic member having an opening, andsignal producing means mounted on the loop portion, the signal producingmeans including a member movable through the opening in a directiontoward the second surface of the inelastic strap upon movement of thespaced portions away from each other.

References Cited in the file of this patent UNITED STATES PATENTS2,428,980 McCann Oct. 14, 1947

